Knowledge Bank

High resolution FTIR spectra of the $\nu 2/\nu 4$ and the $\nu 1/\nu 3$ bands of $\mathrm{<mrow\; data-mjx-texclass="ORD">120</mrow>}SnD4$ have been measured with a Bruker 120 HR interferometer. The sample was prepared under vaccum using a two step synthesis. The $\nu 2/\nu 4$ region ($425-620cm-1$) was studied using a liquid He-cooled bolometer, while an MCT detector was used in the $\nu 1/\nu 3$ region ($1275-1455cm-1$). The resolution of the spectra are $0.0033cm-1$ and 0.0024$cm-1$, respectively. The measurement of the first and second stretching overtones is in progress, too. The results will be compared with those of normal stannane, $SnH4$. In the case of normal stannane vibrational localisation has been found to take place in stretching vibrational overtones. Thus the dynamical symmetry of stannane, a spherical top molecule, has been found to become that of a prolate symmetric top.